…is postponed until next year. This is interesting, politically:
In one corner, we have the SpaceX Crew Dragon, a successor to the original Dragon capsule it’s been using to deliver supplies to the ISS. The seven-seater vehicle appears to be quite the looker, with fairly large windows to give passengers a stunningly clear view of their journey — a feature you’d definitely appreciate if you were a paying customer. The company already has a solid idea of what to do with the capsule outside of its Commercial Crew responsibilities. In fact, it already sold two seats to take private citizens on a trip around the moon next year … but only if it has already started taking astronauts to the ISS for NASA.
A successful Falcon Heavy flight (hopefully next month) is a necessary, but not sufficient condition for SpaceX to attempt an Apollo 8 recreation (the fiftieth anniversary is almost exactly a year from now). If they do it before they’re flying commercial crew, it will have the appearance of not keeping their eyes on the ball for NASA’s needs. But NASA can control the schedule by throwing up impediments to first flight, and some at the agency might be motivated to see that happen, because it would be politically embarrassing to see a private company do an Apollo 8 re-enactment before the agency can with SLS, causing even more people to question the need for the latter. It will be an interesting year.
Oh, one other point. Amusing to see a woman journalist using the terms “manned” and “unmanned.” I personally try to only use those terms to describe historical events (e.g., Apollo). It appears that “crewed” and “uncrewed” are gaining acceptance, but there remain two problems with that. First, “crewed” sounds like “crude” when verbalized. Second, not everyone who flies will be crew. Maybe we need to start saying “humanned” spaceflight.
“Maybe we need to start saying “humanned” spaceflight.”
That’s “humynned” you un-PC neanderthal 😉
But what if one of the astronauts identifies as a unicorn?
Math question: The article says that “NASA’s own space shuttle had a safety rate of one fatal accident in 90 flights”. I can trace this figure back to 2015 when Justin Kerr, manager of the Spacecraft Office in the Commercial Crew Program, gave an overview of a NASA ASAP meeting which included the statement that the Shuttle program ended with a LOC ratio of “about 1 in 90”.[1] This is clearly not coming from a simplistic division of 2/135 which is 1 in 67.5, so what goes into the calculation of their more optimistic value?
[1] https://www.nasaspaceflight.com/2015/05/nasa-evaluating-commercial-loss-crew-mishap/
I suspect Justin got his number from this briefing.
Looking at the report, I suspect they ran a PRA based on known and analyzed failure rates. But another way to consider is the first incident happened after 24 flights (1:25). The next event happened after 86 flights (1:87). Losses are painful, but they can be learning events. NASA did learn from the pain. It’s reasonable to consider another 69 missions before another Loss of Crew or Vehicle event, which would make 1:90. Also consider, the estimate was based on the risk when the program ended, which was a different system than the start of the program.
Thank you, Leland, for the explanation and especially for digging up that link!
Yes, without digging into the numbers, I was going to say it was something like that, and a lot more complicated than simply dividing LOC events by total flights. OTOH, there were still sufficiently few flights to have much statistical confidence in the numbers.
Yeah, I still remember getting complaints about not including confidence interval in a failure rate analysis report I did. Actually I had, but I pointed out that even at the most optimistic 95% CI, the particular item would fail earlier than a second opportunity to repair it. There are 93 pages at the link, and the CI is not present or at least not obvious.
Plus the advanced age of the vehicles would be a factor.
It would be a negative factor, but yeah. Still, the structure was designed for many more cycles. We learned late that the acoustics at the pad were a bit higher than originally thought, so there was some enhanced degradation of the structure factored in.
Conversely to the age of the vehicles was the age and intelligence gathered by the long term workforce. The guys at KSC got better at maintaining the fleet. They picked up on things that come from knowing the vessel really well and understanding when things aren’t quite right.
But all this is nice conversation stuff and not all that usable. The fact is missions were greenlit assuming a LOCV of over 1:200, yet now NASA claims statistical reality to be closer to 1:90. The first launch (slide 32) had a PRA at the time for LOCV between 1:1000 – 1:10,000, while the most recent analysis says it was closer to 1:12, which gave a boost to LOC due to the existence of ejection seats that when removed lowered LOCV to 1:10.
Yet we continued to fly, and had no problem hiring astronauts. We were blissfully ignorant. I think you could show this study to 100 people, and then tell them we found an extra ET and were looking for a 7 person crew for STS-136. I bet you would get enough applicants from that 100 people.
“Still, the structure was designed for many more cycles.”
You’re assuming that cycles matter more than age.
If I remember correctly, one reason the shuttles wouldn’t have been able to continue flying without extensive teardowns and rebuilds was because some of the components that were never intended to be replaced were reaching the limits of their design lifetime.
I believe the actuators for the rudder were one of those components, and would have required taking the airframe apart to reach them.
Their retrospective analysis of per flight probability of LOCV through flight 25 is around 1:10. That drops to around 1:37 post-Challenger, largely due to SRB redesign. It bumps up to 1:21 by flight 87 due to increased foam shedding with the banning of CFC-11. This is mitigated via venting holes in ET foam, so along with improved orbiter software, risk is down to 1:47 by flight 96. Post-Columbia risk is down to 1:73 with on-orbit vehicle inspection, repair, and crew rescue. It is brought further down to 1:90 by flight 133 by the addition of late inspection and improved SSME (Main Engine) monitoring.
Integrating these changing probabilities over 135 flights gives an expected loss value of 5.2 flights.
From the article: “In March, ISS crew members even installed a second dock that space taxis can use when they finally start ferrying astronauts to the space station.”
Yeah, after SpaceX splashed the first one. IDA-3 is expected to launch on SpaceX/CRS-16, currently scheduled for August 2018.
In general SpaceX news, Mr. Steven, the payload fairing recovery vessel, is now sporting some rigging on its arms:
https://uploads.tapatalk-cdn.com/20171226/115188ad08a69ba351cc68a7cc26ad3f.jpg
Here is it unrigged, shortly before heading out on its dry run for Friday’s Vandenberg launch.
https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=37727.0;attach=1467406;image
https://pbs.twimg.com/media/DRa5233WAAE2zp8.jpg
Still no indication if it will be have nets or if it will really use “a kind of bouncy castle” as suggested by Mr. Musk back in the spring.
Thanks for the link to Mr. Steven with rigging! I’ve been following fairing recovery with great interest, but hadn’t seen that one.
“Man” has two meanings — one sex-specific and the other not. Western civilization really needs to stop letting fenderheads limit the full scope of the English language.
But McGehee, to fenderheads the dumbing down of humanity is a feature, not a bug.
Use of the word humanity is double-plus ungood. The new NewSpeak work is huwymanity. Report for reeducation immediately. You may bring a single suitcase for your personal belongings. /s
I was shootin’ for double ungood so the two negatives would cancel out, but double plus means I’m screwed!
Unfortunately, appearances, shallow thought, and a little ill-will are the driving forces in proper language these days.
Some people just don’t like that men and women are both humans and that some words refer to them that way.
Rand, it’s not a race at all… the SLS paper rockets will always be more capable than any real rocket others come up with!!!
Until Trump notices perhaps?
“Crewed” does sound crude.
I was just about to suggest “Staffed” but it then occurred to me that term might be taken as phallo-centric as well.
Some companies have been using, “tended.”
I don’t see much difference between crewed and tended but people who get upset about the presence of “man” in any word could get upset about how crewed sounds. Of course they get upset about everything since being upset is the game, so whatever word is used today will be something only the out group says in the not so distant future.
As David Spain says below, we have to consider the robots in this so manned wouldn’t work. Crewed could work but implies some level of humanity. Tended or staffed could work but did anyone ask the robots about this?
“Tended” means a facility that is only occasionally visited by humans.
Hmm, good to know. I figured it was because of the type of activities taking place.
The English language is very accommodating of new words but so few people even bother. It is probably because it is hard to break out of the neuron paths our brain constructs around language.
How about “occupied” flights and “unoccupied” flights? OK, maybe not.
Let’ just say it. Men don’t matter. It must now be referred to as womanned (unless too dangerous.)
Humanned?
Et tu, Rand?
Argh! Rand, can we just dispense with the worry over the non-PC, misogynistic, micro-aggressions? Besides you are totally ignoring this possibility:
https://tinyurl.com/y8q7ljnv
Boeing vs SpaceX is not much of a space race. There wont be a loser because both are guaranteed to win. One could pull ahead commercially but that seems like a different race than what is taking place. I hope they are both successful and that Boeing is able to sell their product to customers other than NASA and if Bigelow chooses them, they are not limited to ULA rides.
This is great but the larger space race is far more exciting. There are so many companies and countries getting into it that it is really hard to say who the contenders will be a decade from now.
Manned space flight->Human space flight
Manned space ship->Human-rated space ship
Space men->Astronauts
Rocket men->Rocket jockies->Rocket Riders->Space flight participants
Rockettes->Rockefeller’s dancers
Unmanned space vehicle->USV (u is short for unhumanned I guess)
Sam, your alternate’s do not mean the same thing. Why allow leftist to control our language? Defeat is not acceptable… especially without the wimpiest of fights. Humanned is not a word and will not be. Ridicule is the only appropriate response.
If ‘speak English’ is a micro-aggression how would they like some real aggression?
NASA is planning an interstellar mission for 2069, may head to nearby Alpha Centauri
“…A tentative mission is currently being outlined that would see NASA send a spacecraft on an interstellar mission to explore the Alpha Centauri system.
The proposed journey, which was revealed by scientists with NASA’s Jet Propulsion Laboratory at the 2017 Geophysical Union Conference and reported by New Scientist, was born out of a budget mandate to make progress on interstellar travel. ”
http://bgr.com/2017/12/19/alpha-centauri-mission-nasa-2069/
Generally, I don’t like it. Mainly because NASA should be exploring the Moon.
But one can pose the question when will the Moon become practical gateway to our solar system and beyond.
Or if there was commercial lunar water mining, when would the Moon become practical gateway.
It seems to me that if imagine there going to be towns on Mars by 2050, it would answer the question- likely by 2050 that the Moon is practical gateway or there is some kind of gateway [and I would exclude a “LEO only” as the gateway].
It seems to me that the Moon and Mars needs some exploration before
lunar water mining and Mars towns are possible.
If mining locations are found in lunar polar regions, then money is invested to mine the lunar water and use lunar water for making rocket fuel which can sold for about $2000 per lb [or LOX about $1000 and LH2 for about $4000 per lb which about +1000 tons of water and rocket fuel is made over 5 year period- something like 100 tonnes per year and doubling production every year or so]. I would say that within the first decade of such operation, the use of lunar rocket fuel is mostly confined to a lunar use. Or not directly related to getting to Mars, elsewhere or the Stars.
Or another way to say this, is the price of lunar rocket fuel has lower by significant amount before it’s exported beyond lunar low orbit. Or one might need to make much more than 1000 tons of rocket fuel per year-
though perhaps only 2000 to 4000 tons per year.
A limiting factor doesn’t seem to be mining lunar water, but rather having the energy to make rocket fuel. You need a energy market at lunar poles which anyone can buy electrical power at price range of $50 to $75 per kW hour [or less]. And important aspect of that price is related the ability to get as much power as you need and whenever you need it.
Or one’s expansion is not limited by energy rationing or shortages, nor that one given more power than you need [and expected to pay for it]. Or talking about a retail price [though more like industrial rather than residential].
Now having any kind of electrical market anywhere is space could be relevant to a interstellar exploration mission- one could possible use beamed power. And interstellar trips require a lot of energy.
Having electrical or chemical or any kind of energy market in space anywhere would be important and it seems main component of a gateway.
Now the results of exploring the lunar polar region may indicate that the Moon is not a useful destination in near term. Or you might need to start energy market somewhere else. And it should noted that we have a second moon, quite bit further away, but it’s asteroid so it doesn’t have the delta-v requirement of landing and leaving as the Moon has.
It’s seems priority should explore lunar poles, then explore Mars.
But in terms of private exploration, the second moon has advantages- it seems the best choice at this point in time.
With Mars exploration, NASA focus should be to find the best locations for Mars towns. And having billions of tonnes of water available at low cost within 100 km would important factor for Mars town site.
Though first thing NASA needs to find is good locations for exploration
bases- which require less water, one could even get the water from the atmosphere. Or cost of water at Mars surface could higher than cost of lunar water- it’s not major factor for small exploration crews [which probably shouldn’t depend on mars food production- ship most of food needed from Earth.